PT-2016-3291 · Openbsd+7 · Openssh+7

Published

2016-01-14

·

Updated

2026-05-29

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CVE-2016-0778

CVSS v3.1

8.1

High

VectorAV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Name of the Vulnerable Software and Affected Versions OpenSSH versions 5.x through 7.x before 7.1p2
Description The issue is related to the roaming read and roaming write functions in OpenSSH, which do not properly maintain connection file descriptors when certain proxy and forward options are enabled. This can lead to a denial of service or possibly other impacts due to a heap-based buffer overflow. The vulnerability can be exploited by remote servers requesting many forwardings. It is also caused by improper bounds checking by the packet write wait() and ssh packet write wait() API functions when a ProxyCommand and either ForwardAgent or ForwardX11 are used.
Recommendations For OpenSSH versions 5.x through 7.x before 7.1p2, update to version 7.1p2 or later to resolve the issue. As a temporary workaround, consider disabling the roaming read and roaming write functions until a patch is available. Restrict access to the packet write wait() and ssh packet write wait() API functions to minimize the risk of exploitation. Avoid using the ProxyCommand option along with ForwardAgent or ForwardX11 in the affected API endpoints until the issue is resolved.

Exploit

Fix

DoS

Buffer Overflow

Weakness Enumeration

Related Identifiers

ALT-PU-2016-1200
ALT-PU-2024-3921
ALT-PU-2024-4077
ALT-PU-2024-4467
ALT-PU-2024-9513
BDU:2019-01914
CESA-2016_0043
CVE-2016-0778
DLA-387-1
DSA-3446-1
MGASA-2016-0022
OPENSUSE-SU-2016_0127-1
OPENSUSE-SU-2016_0128-1
OPENSUSE-SU-2016_0145-1
OPENSUSE-SU-2024:10174-1
RHSA-2016:0043
RHSA-2016_0043
SUSE-SU-2016:0117-1
SUSE-SU-2016:0118-1
SUSE-SU-2016:0119-1
SUSE-SU-2016:0120-1
USN-2869-1

Affected Products

Alt Linux
Centos
Ibm Aix
Junos
Openssh
Red Hat
Suse
Ubuntu